Six men are being questioned following the seizure of cash and firearm ammunition in West Dublin on Thursday.
As part of Operation Thor, six houses were searched in Clondalkin, Palmerstown, Lucan and Balgaddy.
A motorbike, a substantial amount of cash, firearms components and ammunition were seized.
The six men were arrested on foot of existing warrants issued by the courts.
While one man was arrested under Section 30 of the Offences Against the State Act under the firearms act.
He remains in custody at Ronanstown Garda Station.
